Update vue-i18n@6x support
Update vue-i18n@6x support

i18n returns renderSlot (vm._t) function instead i18n.t
https://kazupon.github.io/vue-i18n/en/api.html
immissile/m-element,renxia/element,Kingwl/element,JavascriptTips/element,ElemeFE/element,baiyaaaaa/element,huguangju/element,huguangju/element,immissile/m-element,ElemeFE/element,Leopoldthecoder/element-1,Raganof/element,Raganof/element,Leopoldthecoder/element-1,baiyaaaaa/element,Kingwl/element,JavascriptTips/element,renxia/element